IGCP 565 Project Workshops
IGCP 565 Workshop 4: Integration of geodetic observations and products in models of the hydrological cycle
Support for water management through hydrological models and data assimilation
November 21-22, 2011
Johannesburg, South Africa
Water resources analysis and monitoring with the GRACE Data Assimilation System
B. F. Zaitchik (1); M. Rodell (2); R. H. Reichle (3); B. Li (4, 2); R. Houborg (4, 2); J. D. Bolten (2)
1. Earth & Planetary Sciences, Johns Hopkins University, Baltimore, MD, United States.
2. Hydrological Sciences Branch, NASA Goddard Space Flight Center, Greenbelt, MD, United States.
3. Global Modeling and Assimilation Office, NASA Goddard Space Flight Center, Greenbelt, MD, United States.
4. Earth System Sciences Interdisciplinary Center, University of Maryland, College Park, MD, United States.
The Gravity Recovery and Climate Experiment (GRACE) has provided unprecedented observations of water storage dynamics at the basin to continental scale. In order to realize the full potential of GRACE for hydrology, however, GRACE-derived regional-scale, column-integrated, monthly terrestrial water storage (TWS) anomalies must be disaggregated horizontally, vertically, and in time. The GRACE Data Assimilation System (GRACE-DAS) was designed to downscale and to disaggregate GRACE TWS observations by assimilating them into the Catchment Land Surface Model using a novel implementation of an Ensemble Kalman Smoother. As we have reported previously, this system improved model skill in the simulation of hydrological states and fluxes at sub-GRACE resolution in the Mississippi basin. Here we report on new developments in GRACE-DAS, including application of the system to North America, Europe, the Middle East, and Africa, progress and conceptual challenges in improving the assimilation algorithm, and the use of newly available GRACE TWS solutions in GRACE-DAS. Emerging directions in GRACE-DAS development, including multi-sensor assimilation systems and application to coupled regional climate models, will also be discussed.